Ok, well, "going along with it just for him" is another kink I really get into. Otherwise there would not have been any anal sex. After some practice I really enjoy it.
There are a lot of kinks I don't understand, and I don't really need to. It's someone else's thing, not my thing. If the sight/feel of latex doesn't do anything for me, but leather does, well, can I really understand someone else's feelings for latex? Not really, although I can approximate it by thinking it must be like what leather is to me.
So maybe your feeling about pain is what someone else feels about humiliation. It's just hot.